OpenAPI Editor and Visualizer
Design your API in the browser. Ship the spec in minutes.
Free2,353 impressions#5 of its week
A free browser-based editor to write, import and validate Swagger/OpenAPI specs with live documentation preview.
- for
- API designers and developers who need quick, no-signup spec editing.
- pricing
- free
Key features
- Live documentation preview — Renders visual API docs side-by-side as you type.
- Inline linting & validation — Flags syntax and governance issues in real time.
- Multi-format support — Handles Swagger 2.0 and OpenAPI 3.0-3.2 in YAML or JSON.
- No account required — Use the editor instantly without signup or installation.
- Import from URL or file — Paste a spec, open a local file, or fetch from a URL (up to 10 MB).
- Generate Postman collection — Creates a two-way sync collection that can be run and tested.
Use cases
- Draft an API spec quickly in the browser
- Validate an existing OpenAPI file before importing to Postman
- Generate a runnable Postman collection from a spec
- Share live documentation with stakeholders without hosting
- Edit a spec fetched from a remote URL up to 10 MB
OpenAPI Editor and Visualizer FAQ
What does this free Swagger / OpenAPI editor give you?+
It lets you write, paste or import a definition, supports Swagger 2.0 and OpenAPI 3.0-3.2 in YAML/JSON, renders docs instantly, flags syntax and governance issues, and requires no account.
Which formats are supported?+
Swagger 2.0, OpenAPI 3.0, 3.1 and 3.2, in either YAML or JSON; format is detected automatically.
Can I import Swagger specs into Postman?+
Yes, you can import Swagger 2.0 specs directly and generate a Postman collection that stays in two-way sync.
Does Postman upload my OpenAPI definition?+
Definitions are parsed in the browser; importing from a URL sends the URL to Postman's Cloud Agent, which fetches and returns the spec without creating an account.
What are the signed-out limits?+
Typed, pasted, and local-file definitions have no usage quota; URL imports accept responses up to 10 MB, and drafts are not auto-saved after reload.
Can I turn this spec into something I can actually run and test?+
Yes, the editor can generate a Postman collection that you can run and test, staying in sync as the spec evolves.
Summarized by DevHunt from postman.com · Sep 28, 2026. Details may change; check the official site.
